Dublin City Councillor Hazel Chu has been elected as deputy leader of the Green Party.
Louth councillor Marianne Butler was the other candidate in the internal party contest.
All paid up members who have been in the Green Party for six months were entitled to vote in this election, where 63.2% of members backed the Dublin councillor.
Ms Chu said climate action, nature restoration, social justice and an equal economy are not niche issues, but are the core priorities of modern politics.
"We are strongest when we act as one movement, sharing ideas, talent and ambition across borders," she said.
Marianne Butler described the campaign as a healthy and constructive process for the Green Party.
"While we are all committed to rebuilding our party, members saw different visions, for how that should happen.
"That's a good thing and I hope that conversation will continue," she said.
